2009年6月18日 星期四

巴西巴西亞東北部產麗脂鯉兩新種

文獻來源: Zanata, A.M. & Camelier, P. (2009): Astyanax vermilion and Astyanax burgerai: new characid fishes (Ostariophysi: Characiformes) from Northeastern Bahia, Brazil. Neotropical Ichthyology, 7 (2): 175-184.

Abstract Two new Astyanax species, A. vermilion, from rio Almada and rio Cachoeira, and A. burgerai, from rio Almada, Bahia State, Brazil, are described. Astyanax vermilion is distinguished from most of its congeners and from all other Astyanax species known from northeastern Brazilian drainages by having distal portion of pelvic fins dark, a combination of sexually dimorphic characters, posteroventral portion of body and fins (except pectoral) reddish in life, and inconspicuous humeral and caudal spots. It also differs by having highest body depth just anterior of dorsal-fin origin, 32-34 lateral-line scales, and presence of one or two maxillary teeth. Astyanax burgerai is diagnosed by the presence of two vertically elongated humeral blotches, absence of a conspicuous and broad dark midlateral stripe (at least on anterior half of body), body highest along vertical slightly behind midlength of pectoral fin, 31-34 lateral-line scales, and two or three teeth on premaxillary outer series.